פּירוש אויף שמות 18:18

נבל תבל — Explain this as the Targum does: thou will certainly become weary. Its meaning expresses the idea of withering, old French flestre, just as. (Jeremiah 8:13) “and the leaf is withered (נבל)”; (Isaiah 34:4) “as withereth (כנבל) the leaf from off the vine” — the meaning being that it becomes shrivelled through the heat and through the frost, and so its strength diminishes and it becomes, as it were, weary, and falls from off the vine (מגפן)‎.

נבול תבול, “you will definitely become worn out;” the word is similar to ערבוב, “being confused.” Compare Genesis 11,7 Where G-d confused man’s languages. Yitro felt that both Moses and the litigants would become confused. One would shout that he wanted to be heard next and another litigant would also shout. As a result, Moses himself would become confused since he would be unable to hear each person correctly. And they would also be unable to hear what you say.

גם אתה, the word גם is meant to include Aaron and Chur. This seems odd, as Chur was killed during the incident with the golden calf as explained by Rashi on Exodus 32,5 on the words ויבן מזבח לפניו, where Rashi says the word מזבח is to be read as if the vowels had been mi-zavoach; we would have to answer that that interpretation was based on the scholars who claim that Yitro arrived before the revelation at Mount Sinai, at which time Chur had still been alive.